Ricardo Del Sol

Swansea University | SWAN · Institute of Life Science "ILS"

RNA interference (RNAi) methods for insects are often limited by problems with double-stranded (ds) RNA delivery, which restricts reverse genetics studies and the development of RNAi-based biocides. We therefore delegated to insect symbiotic bacteria the task of: (i) constitutive dsRNA synthesis and (ii) trauma-free delivery. RNaseIII-deficient, ds...

Obligate bacterial symbionts are widespread in many invertebrates, where they are often confined to specialized host cells and are transmitted directly from mother to progeny. Increasing numbers of these bacteria are being characterized but questions remain about their population structure and evolution. Here we take a comparative genomics approach...

The transition from primary to secondary metabolism in antibiotic-producing Streptomyces correlates with expression of genes involved in stress responses. Consequently, regulatory pathways that regulate specific stress responses are potential targets to manipulate to increase antibiotic titres. In this study, genes encoding key proteins involved in...

Dps proteins are members of an extensive family of proteins that oxidise and deposit iron in the form of ferric oxide, and are also able to bind DNA. Ferroxidation centres are formed at the interface of anti-parallel dimers, which further assemble into dodecameric nanocages with a hollow core where ferric oxide is deposited. Streptomyces coelicolor...

Mediator, an evolutionary conserved large multisubunit protein complex with a central role in regulating RNA polymerase II-transcribed genes, serves as a molecular switchboard at the interface between DNA binding transcription factors and the general transcription machinery. Mediator subunits include the Cdk8 module, which has both positive and neg...

We report the 4,385,577-bp high-quality draft assembly of the bacterial symbiont Rhodococcus rhodnii strain LMG5362, isolated from the gut of Rhodnius prolixus (Hemiptera, Reduviidae, Triatominae), the principle vector of the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. This sequence might provide useful information for sub...

Dps proteins are found almost ubiquitously in bacterial genomes and there is now an appreciation of their multifaceted roles in various stress responses. Previous studies have shown that this family of proteins assemble into dodecamers and their quaternary structure is entirely critical to their function. Moreover, the numbers of dps genes per bact...

Antibiotic-producing Streptomyces are complex bacteria that remodel global transcription patterns and their nucleoids during development. Here, we describe a novel developmentally regulated nucleoid-associated protein, DdbA, of the genus that consists of an N-terminal DNA-binding histone H1-like domain and a C-terminal DksA-like domain that can pot...

Phylogenetic reconstruction revealed that most Actinobacterial orthologs of S. coelicolor SCO2837, encoding a metal-dependent galactose oxidase-like protein, are found within Streptomyces and were probably acquired by horizontal gene transfer from fungi. Disruption of SCO2837 (glxA) caused a conditional bld phenotype that could not be reversed by e...

GC content (%) of Streptomyces and S. aurantiaca genomes and SCO2837 (glxA) orthologs used in GC content comparisons. Only assembled genome sequences were included. ORF name is indicated when more than one glxA-like sequence per genome is present. (DOC)

Diagram representing SCO2837 (glxA) genetic locus and DNA fragments used in sub-cloning experiments. The position of transposon insertions is indicated by gray vertical arrows, while the putative promoter predicted by PromBase is indicated by a striped arrow with chromosome position indicated. Refer to [19] for a detailed map of Tn5062. (TIF)

Neighbour-Joining Bootstrap phylogenetic tree generated using protein sequences displaying similar domain composition and organisation to GlxA. Numbers at branch nodes indicate bootstrap values. (TIF)

[This corrects the article on p. e25593 in vol. 6.].

The DpsA protein plays a dual role in Streptomyces coelicolor, both as part of the stress response and contributing to nucleoid condensation during sporulation. Promoter mapping experiments indicated that dpsA is transcribed from a single, sigB-like dependent promoter. Expression studies implicate SigH and SigB as the sigma factors responsible for...

To date, the function of only two of the 34 predicted serine/threonine protein kinases (STPKs) of Streptomyces coelicolor has been described. Here we report functional analysis of pknB and two linked genes, fhaAB, encoding forkhead-associated (FHA) domain proteins that are part of a highly conserved gene locus in actinobacteria. In contrast to the...

Enriched phosphoproteomes of (A) M145, (B) pknB mutant and (C) fhaAB mutant. Cultures were grown on NE medium for 48 h and phosphoproteins subsequently enriched from cell extracts by affinity chromatography using a phosphoprotein purification kit (Qiagen). Samples were subsequently analysed by SDS‐PAGE, followed by detection of phosphoproteins with...

A simple and high-throughput transposon mediated mutagenesis system employing in vitro shuttle transposon mutagenesis has been used to systematically mutagenise the Streptomyces coelicolor genome. To achieve the highest coverage, a new ordered cosmid library was also constructed. Individual cosmids from both the existing and new libraries were disr...

An esx locus, related to the multiple esx loci of Mycobacterium tuberculosis, is conserved in all sequenced Streptomyces genomes, where it is associated with the developmental regulatory gene bldB. Here we demonstrate that the esxBA operon, comprising part of the locus, has a novel morphogenetic function in the model species Streptomyces coelicolor...

The Dps protein, a member of the ferritin family, contributes to DNA protection during oxidative stress and plays a central role in nucleoid condensation during stationary phase in unicellular eubacteria. Genome searches revealed the presence of three Dps-like orthologues within the genome of the Gram-positive bacterium Streptomyces coelicolor. Dis...

As free-living non-motile saprophytes, Streptomyces need to adapt to a wide range of environmental conditions and this is reflected by an enormous diversity of regulatory proteins encoded by, for example, the genome of the model streptomycete Streptomyces coelicolor. In this organism, we have identified a new osmoregulation gene, osaC, encoding a m...

The conserved rodA and ftsW genes encode polytopic membrane proteins that are essential for bacterial cell elongation and division, respectively, and each gene is invariably linked with a cognate class B high-molecular-weight penicillin-binding protein (HMW PBP) gene. Filamentous differentiating Streptomyces coelicolor possesses four such gene pair...

Cell surface changes that accompany the complex life cycle of Streptomyces coelicolor were monitored by atomic force microscopy (AFM) of living cells. Images were obtained using tapping mode to reveal that young, branching vegetative hyphae have a relatively smooth surface and are attached to an inert silica surface by means of a secreted extracell...

The 45/47 kDa APA protein (Rv1860) of Mycobacterium tuberculosis was produced by Streptomyces lividans. The recombinant protein could be recovered from the culture medium of an S. lividans clone containing the apa gene under control of the promoter and signal sequence of the Streptomyces coelicolor agarase gene. The recombinant protein production w...

The product of the crgA gene of Streptomyces coelicolor represents a novel family of small proteins. A single orthologous gene is located close to the origin of replication of all fully sequenced actinomycete genomes and borders a conserved gene cluster implicated in cell growth and division. In S. coelicolor, CrgA is important for coordinating gro...

On solid media, the reproductive growth of Streptomyces involves antibiotic biosynthesis coincident with the erection of filamentous aerial hyphae. Following cessation of growth of an aerial hypha, multiple septation occurs at the tip to form a chain of unigenomic spores. A gene, crgA, that coordinates several aspects of this reproductive growth is...

We describe a novel filamentous phage, designated VGJφ, isolated from strain SG25-1 of Vibrio cholerae O139, which infects all O1 (classical and El Tor) and O139 strains tested. The sequence of the 7,542 nucleotides of the phage genome reveals that VGJφ has a distinctive region of 775 nucleotides and a conserved region with an overall genomic organ...

Para estudiar la producción secretora de proteínas heterólogas en cepas de Actinomicetos fue seleccionado inicialmente el interferón alfa 2b humano recombinante (IFNα2bhum-rec) como proteína modelo. Para ello fueron construidos los vectores bifuncionales Escherichia coli-Streptomyces pUWL-Δ2 y pUWL-7.5; los cuales utilizan, como señal de secreción,...

A chromosomal DNA fragment from Streptomyces peucetius SGF-107 (a producer of daunomycin) which activates the biosynthesis of two polyketide antibiotics, daunomycin and actinorhodin, has been cloned and sequenced. Partial DNA sequencing of the activating fragment revealed the presence of two open reading frames whose deduced products exhibit simila...

In the present parer we describe the isolation of a DNA fragment from a Mycobacterium bovis (BCG) genomic library capable of activating actinorhodin biosynthesis in Streptomyces coelicotor ATCC 10147 and Streptomyces lividans TK54.